We've seen all manner of optical illusions in recent years, from rotating horses to countless objects that appear to be moving despite being still. But just when it feels like we've seen them all, it seems we're about to receive another lesson in how our eyes can trick us from none other less one of the biggest planets in the solar system.
Saturn, the sixth planet from the Sun, is best known for its rings, but apparently they're going to disappear. Visible from Earth using telescopes, these formations of orbiting ice particles, rock and space dust have fascinated astronomers since the times of Galileo. But that might not be the case in 2025.
According to the video from NASA above, Saturn's rings are disappearing long term, but that's not the immediate issue. The rings will still be there in 2025, we just won't be able to see them.
Saturn's seven rings are very deep, but they're only about ten metres thick, and how well we can see them depends on Saturn's alignment with Earth. Saturn is currently tilted at about a 9 degree angle, which makes it possible to see the rings. But next year, that tilt will be just 3.7 degrees. And in 2025, Saturn's axis will be vertical with the rings a horizontal strip parallel to Earth. They will be too narrow to see.
Saturn's optical illusion will not be permanent, however. The planet has a 29.5-year cycle and will slowly start to reveal the underside of the rings as it starts to tilt again, reaching its maximum tilt in 2032. However any astrophotographers hoping to capture the rings will need to do it in the coming months or wait out 2025 (see how one photographer takes stunning optical illusion photos of the moon).